Fixed #25434 -- Documented HttpRequest.site and created a section for middleware attributes.

Attributes

----------

All attributes should be considered read-only, unless stated otherwise below.

``session`` is a notable exception.

All attributes should be considered read-only, unless stated otherwise.

.. attribute:: HttpRequest.scheme

    underscores in WSGI environment variables. It matches the behavior of

    Web servers like Nginx and Apache 2.4+.

.. attribute:: HttpRequest.user

    An object of type :setting:`AUTH_USER_MODEL` representing the currently

    logged-in user. If the user isn't currently logged in, ``user`` will be set

    to an instance of :class:`django.contrib.auth.models.AnonymousUser`. You

    can tell them apart with

    :meth:`~django.contrib.auth.models.User.is_authenticated`, like so::

        if request.user.is_authenticated():

            # Do something for logged-in users.

        else:

            # Do something for anonymous users.

    ``user`` is only available if your Django installation has the

    :class:`~django.contrib.auth.middleware.AuthenticationMiddleware`

    activated. For more, see :doc:`/topics/auth/index`.

.. attribute:: HttpRequest.session

    A readable-and-writable, dictionary-like object that represents the current

    session. This is only available if your Django installation has session

    support activated. See the :doc:`session documentation

    </topics/http/sessions>` for full details.

.. attribute:: HttpRequest.urlconf

    Not defined by Django itself, but will be read if other code (e.g., a custom

    will use its value as the ``current_app`` argument to

    :func:`~django.core.urlresolvers.reverse()`.

Attributes set by middleware

----------------------------

Some of the middleware included in Django's contrib apps set attributes on the

request. If you don't see the attribute on a request, be sure the appropriate

middleware class is listed in :setting:`MIDDLEWARE_CLASSES`.

.. attribute:: HttpRequest.session

    From the :class:`~django.contrib.sessions.middleware.SessionMiddleware`: A

    readable and writable, dictionary-like object that represents the current

    session.

.. attribute:: HttpRequest.site

    From the :class:`~django.contrib.sites.middleware.CurrentSiteMiddleware`:

    An instance of :class:`~django.contrib.sites.models.Site` or

    :class:`~django.contrib.sites.requests.RequestSite` as returned by

    :func:`~django.contrib.sites.shortcuts.get_current_site()`

    representing the current site.

.. attribute:: HttpRequest.user

    From the :class:`~django.contrib.auth.middleware.AuthenticationMiddleware`:

    An instance of :setting:`AUTH_USER_MODEL` representing the currently

    logged-in user. If the user isn't currently logged in, ``user`` will be set

    to an instance of :class:`~django.contrib.auth.models.AnonymousUser`. You

    can tell them apart with

    :meth:`~django.contrib.auth.models.User.is_authenticated`, like so::

        if request.user.is_authenticated():

            ... # Do something for logged-in users.

        else:

            ... # Do something for anonymous users.

Methods

-------